Patent · US Expired

Multi-function car door closure warning system

US5121098A · kind A · utility

24Cited by
5References
6Claims
0Family size

Inventor

Key dates

Filing dateApr 29, 1991
Grant dateJun 9, 1992
Priority date
Expiry dateApr 29, 2011

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF21S43/14
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

A multi-function car door closure warning sensor includes a main module secured to a car door adjacent to an edge thereof, and an auxiliary module secured to the car body and adjacent with the main module, when the car door is in a closed position. A battery, a first soft magnetic pole piece with an attached normally closed magnetic switch, a buzzer, two sets of L.E.D.'s, and an L.E.D. control circuit are disposed within the main module. A permanent magnet with an atached second soft magnetic pole piece are disposed within the auxiliary module. Whereby, when the door is properly closed, the first and second soft magnetic pole pieces are aligned and separated by a small gap. The permanent magnet induces a magnetic field in the first pole piece which causes the magnetic switch to open. When the car door is not properly closed, no magnetic field is induced in the first pole piece causing the magnetic switch to close, activating the buzzer and L.E.D. control circuit, which causes the two sets of L.E.D.'s to flash on and off intermittently in see-saw fashion.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.